SimpleITK Bspline image representation

Dear all,
I am trying to understand this paper [1] about B-spline. Is there a SimpleITK example to get a B-Spline representation of an image?
Thanks in advance!

[1] Splines - A perfect fit for signal and image processing

Hello @ibr,

The link to the paper you refer to is missing so not sure what it is you are looking for. If you are asking about B-spline based registration we have a notebook for that. If this is something else, please post the paper details so we’ll know what it is you want.

@zivy

Thanks for your quick response and sorry for forgetting adding the link to the paper. I just updated the post and added a link to the paper. It is a popular paper by Unser. I am planning to study it and try to create a notebook tutorial out of it.

The notebook example you added looks interesting but I think it is about image registration. For now, I am interested to know:

  • how to compute the B-Spline control points of an image?
  • how to use these control points to re-create the image?
  • how to get the image derivative using the B-spline representation?

Hello @ibr,

Got it, that notebook has nothing to do with what you want.

In SimpleITK we only exposed the option of BSpline interpolation as a constant to the ResampleImageFilter. This is based on the work of Unser and others as documented in the original ITK BSplineInterpolateImageFunction class. We do not expose the functionality that you want as it is not “Simple” and SimpleITK is a simplified interface.

For what you are looking you should go to ITK (not sure that it provides the image derivative using the B-spline representation, but the ITK code should be a good start).

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